Report (142) Statewide Alternate Method
July 2014
State of UreSon
Building Codes Division No. 08-05
2012 International Existing Building Code and
Better Buildings for Oregon 2014 Oregon Structural Specialty Code, Chapter 34
(Ref.: ORS 455.060)
Statewide Alternate Methods are approved by the Division administrator in consultation with the
appropriate advisory board. The advisory board's review includes technical and scientific facts of the
proposed alternate method. In addition:
• Building officials shall approve the use of any material, design or method of construction
addressed in a statewide alternate method;
• The decision to use a statewide alternate method is at the discretion of the designer; and
• Statewide alternate methods do not limit the authority of the building official to consider other
proposed alternate methods encompassing the same subject matter.
Code Edition: 2012 International Existing Building Code(IEBC)
2014 Oregon Structural Specialty Code (OSSC)
Code Section: OSSC Chapter 34
Date: October 1, 2008 (Issued)
May 5, 2010 (Updated)
July 1, 2014 (Updated)
Initiated by: Building Codes Division (BCD)
Subject: Use of the 2012 International Existing Building Code (IEBC) Chapter 34
Background:
Chapter 34 of the OSSC (based on the 2012 International Building Code)regulates the repair,
alteration, change of occupancy, and addition of existing buildings. It principally provides two paths
for compliance;a"prescriptive compliance method"and a"performance compliance method."
Discussion:
The IEBC, as promulgated by the International Codes Council, expands the provisions of OSSC
Chapter 34 and adds a third approach known as the"work area compliance method"which is based
on the level of work performed. The intent of the IEBC is to provide increased flexibility in the use of
alternative approaches to achieve compliance with minimum requirements to safeguard the public
health, safety and welfare.Designers may not mix and match compliance paths.
Seismic Rehabilitation: The IEBC provides 2 options for the seismic retrofit of existing buildings; 1)
Appendix A and 2)ASCE 31 (Seismic Evaluation of Existing Buildings) in conjunction with ASCE
41 (Seismic Rehabilitation of Existing Structures). These standards are adopted insofar as they relate
to the repair, alteration,change of occupancy,and addition to existing buildings.
Building Codes Division ♦ Department of Consumer and Business Services ♦ State of Oregon ;f.;' ')
1535 Edgewater St.NW, Salem,OR 97304 • P.O.Box 14470, Salem, OR 97309-0404 r
503-378-4133 • Fax: 503-378-2322 • bcd.oregon.gov �;,,
•
Local adoption of a Seismic Rehabilitation Plan(ORS 455.020 {4}): This statute states in part:
"Pursuant to the regulation of dangerous buildings, a municipality may adopt seismic rehabilitation
plans that provide for phased completion of repairs that are designed to provide improved life safety
but that may be less than the standards for new buildings."(Emphasis added). When a local
municipality adopts a seismic rehabilitation plan as noted in statute, it is a separate requirement from
those seismic rehabilitation upgrades that are required as part of an alteration,repair,change of
occupancy or addition. In brief,municipalities may adopt additional triggers requiring compliance
with the local seismic rehabilitation plan. Examples would include:
1. re-roofing,
2. cost threshold of remodel,
3. change of occupancy to a different relative hazard classification, essential facilities
In addition,the locally adopted seismic rehabilitation plan may specify a specific seismic
rehabilitation standard(i.e.,ASCE 41,Appendix A of the IEBC, etc.).
The IEBC also contains"Resource A" entitled; "Guidelines on Fire Ratings of Archaic Materials
and Assemblies."Resource A is only a guideline and is not intended to be a document for adoption.
Accordingly, it is not part of this alternate method.
The technical and scientific facts of this alternate method have been reviewed by the Building Codes
Structures Board.
Conclusion:
This alternate method is applicable to the occupancy categories covered in the Oregon Structural
Specialty Code and administered through chapter 1 of the same.
Alterations,repairs, additions and changes of occupancy to existing structures shall be permitted to
comply with the 2012 International Existing Building Code as amended herein. All 2012 International
Existing Building Code references to other codes are as defined in Chapter 2, of the Oregon Structural
Specialty Code.
The following portions of the International Existing Building Code are not adopted by the State of
Oregon. Subject matter contained therein shall comply with applicable sections of the Oregon
Structural Specialty Code,the Oregon Mechanical Specialty Code,the Oregon Electrical Specialty
Code,the Oregon Boiler and Pressure Vessel Safety Code and the Oregon Plumbing Specialty Code:
1. All portions of Chapter 1,Administration, except Sections 101.2, 101.4, and 101.6
2. Section 115 -Unsafe structures and equipment. (May be adopted by local ordinance)
3. Section 116-Emergency Measures(May be adopted by local ordinance)
4. Section 117 -Demolition(May be adopted by local ordinance)
5. All references to R-3 Occupancies
6. All references to The International Property Maintenance Code(May be adopted by local
ordinance)
7. All references to accessibility. See 2014 OSSC Section 3411
8. All References to Type A and B dwellings
9. All references to historic buildings. See 2014 OSSC Section 3409
10. All references to relocated buildings. See 2014 OSSC Section 3410.1
11. All references to Flood Hazard Areas. Section 2014 OSSC Section 3404.2
12. Sections 607, 808, 1008 -Electrical Provisions
13. Section 608, 809, 1009—Mechanical
14. Section 609, 810, 1010—Plumbing
Page 2 of 11
15. Sections 707, 811, 908 -Energy. See 2014 Oregon Energy Efficiency Specialty Code
16. Section 902.2.1 -Boiler controls
17. Section 804.4-Fire alarm and detection. See 2014 Oregon Fire Code Section 907.3
18. Chapter 15 -Construction Safeguards
19. Chapter 16 -Reference Standards. See 2014 OSSC Chapter 35
20. Elevator standards for existing buildings
21. Platform lifts for existing buildings
22. Appendix B
23. Resource A
The following sections of the IEBC are amended as indicated:
1. Section 1401.2 Applicability. Structures existing prior to July 1,2014,in which there is
work involving additions, alterations or changes of occupancy shall be made to conform to
the requirements of this chapter or the provisions of Chapters 5 through 13.The provisions
of Sections 1401.2.1 through 1401.2.5 shall apply to existing occupancies that will continue
to be, or are proposed to be, in Groups A,B,E,F,M,R, S and U.These provisions shall
not apply to buildings with occupancies in Group H or I.
2. Chapter 3, Section 301.1, 301.1.4.1 and 301.1.4.2: See Structural/Seismic revisions below
3. Chapter 4, Section 402.1,403.1, 404.1, and 407.1: See Structural/Seismic revisions below
4. Chapter 6, Section 602.2, 606.1, 606.2.1, 606.2.2.2,and 606.2.2.3: See Structural/Seismic
revisions below
5. Chapter 7, Section 706.2,and 706.3.1: See Structural/Seismic revisions below
6. Chapter 8, Section 807.5: See Structural/Seismic revisions below
7. Chapter 9, Section 907.4: See Structural/Seismic revisions below
8. Chapter 10, Section 1001.3.1 and 1007.3.1: See Structural/Seismic revisions below.
Contact:
Steve Judson, P.E. Rex Turner
Facilities Engineer Structural Program Chief
503-378-4635 503-373-7755
Steven.W.Judsongoregon.gov Rex.L.Turner@oregon.gov
Tony Rocco
Building Code Specialist
503-373-7529
Anthony.J.Roccoga,oregon.gov
The technical and scientific facts for this Statewide Alternate Method are approved.
(Signature on File) May 5, 2010
Mark Long, Administrator Date
Building Codes Division
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Chapter 3
Section 301.1
SUMMARY OF REVISIONS:
1. Clarify that all new structural members must meet the current IBC.
2. Remove loophole that allows structural design to previous editions of code.
OREGON REVISIONS:
301.1 General. The repair, alteration, change of occupancy, addition or relocation of all existing
buildings shall comply with one of the methods listed in Sections 301.1.1 through 301.1.3 as selected
by the applicant.Application of a method shall be the sole basis for assessing the compliance of work
performed under a single permit unless otherwise approved by the code official. Sections 301.1.1
through 301.1.3 shall not be applied in combination with each other. Where this code requires
consideration of the seismic-force-resisting system of an existing building subject to repair,
alteration, change of occupancy, addition or relocation of existing buildings, the seismic evaluation
and design shall be based on Section 301.1.4 regardless of which compliance method is used. New
structural members added as part of the repair, alteration, change of occupancy or addition
shall comply with the International Building Code.
existence at the time the building or the affected portion of the building was built shall be
considered in compliance with the provisions of this code unless the building is undergoing
more than a limited structural alteration as defined in Section 907.4.3. New structural member;,
added as part of the alteration shall comply with the International Building Code. Alterations of
existing buildings in flood hazard ar s shall comply with Section 701.3.
Section 301.1.4.1
SUMMARY OF REVISIONS:
1. Clarifies that all of the system seismic design parameters must be obtained from ASCE 7 and
incorporates ICC issued errata.
2. Carries forward the intent of the existing amendment to the 2006 IEBC.
3. Under the 2012 IBC the IEBC provisions are only an alternate compliance method, IBC Chapter 34
may still be used.
OREGON REVISIONS:
301.1.4.1 Compliance with IBC level seismic forces. Where compliance with the seismic design
provisions of the International Building Code is required, the procedures shall be in accordance with
one of the following:
1. One-hundred percent of the values in the International Building Code. Where the existing
seismic force-resisting system is a type that can be designated as "Ordinary", values of R,
12o and Cd used for analysis in accordance with Chapter 16 of the International Building
Code shall be those specified for structural systems classified as "Ordinary" in accordance
with Table 12.2-1 of ASCE 7, unless it can is demonstrated that the structural system
satisfies the proportioning and detailing requirements for systems classified as
"Intermediate" or"Special."will provide performance equivalent to that of a"Detailed",
"Intermediate"or"Special"system.
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2. Compliance with ASCE 41 using both the BSE-1 and BSE-2 earthquake hazard levels and
the corresponding performance levels shown in Table 301.1.4.1.
TABLE 301.1.4.1
PERFORMANCE CRITERIA FOR IBC LEVEL SEISMIC FORCES
Risk PERFORMANCE LEVEL PERFORMANCE LEVEL
CATEGORY FOR USE WITH ASCE 41 BSE-1 FOR USE WITH ASCE 41 BSE-2
(Based on IBC Table 1604.5) EARTHQUAKE HAZARD LEVEL EARTHQUAKE HAZARD LEVEL
I Life safety(LS) Collapse prevention(CP)
II Life safety(LS) Collapse prevention(CP)
III Note a,Note b Note a
IV Immediate occupancy(IO) Life safety(LS)
a. Acceptance criteria for RiskCategory III shall be taken as 80 percent of the acceptance criteria specified for Risk Category II performance levels,
but need not be less than the acceptance criteria specified for Occupancy Category IV performance levels.
Section 301.1.4.2
SUMMARY OF REVISIONS:
1. Removes the reference to methods contained in older documents and replaces them with more
modern consensus-based upgrade and evaluation procedures.
2. It further removes the reference to ASCE 31 as an "upgrade"document because ASCE 31 is actually
an "evaluation" document.
OREGON REVISIONS:
301.1.4.2 Compliance with reduced IBC level seismic forces.Where seismic evaluation and design
is permitted to meet reduced International Building Code seismic force levels, the procedures used
shall be in accordance with one of the following:
1. The International Building Code using 75 percent of the prescribed forces. Values of R, no and
Cd used for analysis shall be as specified in Section 301.1.4.1 of this code.
in Appendix A as specified in Items 2.1 through 2.5 shall be deemed to comply with this
section.
2.1 The seismic evaluation and design of unreinforced masonry bearing wall buildings in
Occupancy Category I or II are permitted to be based on the procedures specified in
Appendix Chapter Al.
II are permitted to be based on the procedures specified in Chapter A2.
2.3 Seismic evaluation and design of cripple walls and sill plate anchorage in residential
be based on the procedures specified in Chapter A3.
residential buildings of wood construction in Occupancy Category I or II are permitted to
be based on the procedures specified in Chapter Al.
2.5 Seismic evaluation and design of concrete buildings and concrete with masonry infill
specified in Chapter A5.
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301.1.4.2. •. .- . _ . . - - :. - - -. - •. . - . . - • _ -
'11 and subject to the limitations in Item 'I below.
2,4 Compliance with ASCE 41 using the B SE-1 Earthquake Hazard Level and the performance
level shown in Table 301.1.4.2. The design spectral response acceleration parameters Sxs and
Sxl specified in ASCE 41 shall not be taken less than 75 percent of the respective design
spectral response acceleration parameters SDs and SDI defined by the International Building
Code.
A building that is evaluated and determined to meet ASCE 31 based on the applicable
performance levels as shown in Table 301.1.4.2 is considered to be compliant with reduced IBC
level forces.
TABLE 301.1.4.2
PERFORMANCE CRITERIA FOR REDUCED IBC—LEVEL SEISMIC FORCES RISK CATEGORY
RISK PERFORMANCE LEVEL PERFORMANCE LEVEL
CATEGORY FOR USE WITH ASCE 31 FOR USE WITH ASCE 41 BSE-1
(Based on IBC Table 1604.5) EARTHQUAKE HAZARD LEVEL
I Life safety(LS) Life safety(LS)
TI Life safety(LS) Life safety(LS)
III Notes a,b Note a
IV Immediate occupancy(10) Immediate occupancy(10)
a. Acceptance criteria for RiskCategory III shall be taken as 80 percent of the acceptance criteria specified for Risk Category II performance levels,but
need not be less than the acceptance criteria specified for Risk Category IV perfonnance levels.
b. For RiskCategory III,the ASCE 31 screening phase checklists shall be based on the life safety performance level.
Chapter 4
Section 402.1 —Additions
SUMMARY OF REVISIONS:
IBC Section 3403 and the prescriptive compliance method of the IEBC Section 402 are identical with the
exception of Oregon amendments to Chapter 34 of the IBC. Removing this section of the IEBC and
referencing IBC Section 3403 will include these amendments in the prescriptive path of the IEBC
without having to duplicate all the amendments.
OREGON REVISIONS:
402.1 General.Additions to any building or structure shall comply with the requirements of the
International Building Code, Section 3403.
Delete remainder of IEBC Section 402.
Section 403.1 —Alterations
SUMMARY OF REVISIONS:
IBC Section 3404 and the prescriptive compliance method of the IEBC Section 403 are identical with the
exception of Oregon amendments to Chapter 34 of the IBC. Removing this section of the IEBC and
referencing IBC Section 3404 will include these amendments in the prescriptive path of the IEBC
without having to duplicate all the amendments.
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•
OREGON REVISIONS:
403.1 General.Alterations to any building or structure shall comply with the requirements of the
International Building Code, Section 3404.
Delete remainder of IEBC Section 403.
Section 404.1—Repairs
SUMMARY OF REVISIONS:
IBC Section 3405 and the prescriptive compliance method of the IEBC Section 404 are identical with the
exception of Oregon amendments to Chapter 34 of the IBC. Removing this section of the IEBC and
referencing IBC Section 3405 will include these amendments in the prescriptive path of the IEBC
without having to duplicate all the amendments.
OREGON REVISIONS:
404.1 General.Repairs to any building or structure shall comply with the requirements of the
International Building Code, Section 3405.
Delete remainder of IEBC Section 404.
Section 407.1 - Change of Occupancy
SUMMARY OF REVISIONS:
IBC Section 3408 and the prescriptive compliance method of the IEBC Section 407 are identical with the
exception of Oregon amendments to Chapter 34 of the IBC. Removing this section of the IEBC and
referencing IBC Section 3408 will include these amendments in the prescriptive path of the IEBC
without having to duplicate all the amendments.
OREGON REVISIONS:
407.1 General.Changes of occupancy or use to any building, structure or portion thereof shall
comply with the requirements of the International Building Code, Section 3408.
Delete remainder of IEBC Section 407.
Chapter 6
Section 602.2—New and Replacement Materials
SUMMARY OF REVISIONS:
Modified to be consistent with 2014 OSSC Section 3401.4.2.
OREGON REVISIONS:
602.2 New and replacement materials.Except as otherwise required or permitted by this code,materials
permitted by the applicable code for new construction shall be used. Except for structural repairs
and alterations,b-like materials shall be permitted for repairs and alterations,provided no dangerous
or unsafe condition,as defined in Chapter 2, is created.Hazardous materials, such as asbestos and
lead-based paint, shall not be used where the code for new construction would not permit their use in
buildings of similar occupancy,purpose and location.
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Section 606.1—Structural Repairs
SUMMARY OF REVISIONS:
Clarify that structural repairs must comply with all of the provisions of the OSSC,not just the detailing
provisions.
OREGON REVISIONS:
606.1 General. Structural repairs shall be in compliance with this section and Section 601.2.Regardless
of the extent of structural or nonstructural damage, dangerous conditions shall be eliminated.Regardless
of the scope of repair, new structural members and connections used for repair or rehabilitation shall
comply with the detailing provisions of the International Building Code for new buildings of similar
structure,purpose and location.
Section 606.2.1 —Repairs
SUMMARY OF REVISIONS:
Modified to be consistent with 2014 OSSC section 3405.4.
OREGON REVISIONS:
606.2.1 Repairs for less than substantial structural daage. For damage less than substantial
structural damage, the damaged elements shall be permitted to be restored to their predamage
condition comply with the International Building Code.
Section 606.2.2.2 —Repairs "Compliant"
SUMMARY OF REVISIONS:
Modified to be consistent with 2014 OSSC Section 3405.2.2.
OREGON REVISIONS:
606.2.2.2 Extent of repair for compliant buildings.If the evaluation establishes that the building in its
predamage condition complies with the provisions of Section 606.2.2.1, then the damaged elements
shall be permitted to be restored to their predamage condition repaired such that they comply
with the International Building Code.
Section 606.2.2.3 —Repairs "Noncompliant"
SUMMARY OF REVISIONS:
Modified to be consistent with 2014 OSSC Section 3405.2.3.
OREGON REVISIONS:
606.2.2.3 Extent of repair for noncompliant buildings. If the evaluation does not establish that the
building in its pre-damage condition complies with the provisions of Section 606.2.2.1, then the
building shall be rehabilitated to comply with the International Building Code. provisions of this
section. The wind load for the repair and rehabilitation shall be those required by the building code in
effect at the time of original construction, unless the damage was caused by wind, in which case
construction,but not less than the reduced IBC (strikethrough) level seismic forces .
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Chapter 7
Sections 706.2 & 706.2.1 —Alterations—Level 1
SUMMARY OF REVISIONS:
Modified to be consistent with 2014 OSSC Chapter 16 and ASCE 7
OREGON REVISIONS:
706.2 Addition or replacement of roofing or replacement of equipment. Where addition or
replacement of roofing or replacement of equipment results in additional dead loads, structural
components supporting such reroofing or equipment shall comply with the gravity load
requirements of the International Building Code.
Exceptions:
1. Structural elements where the additional dead load from the roofing or equipment is not
increased by more than 5 percent.
2. Buildings constructed in accordance with the International Residential Code or the
conventional light frame construction methods of the International Building Code and
where the dead load from the roofing or equipment is not increased by more than 5 percent.
3. Addition of a second layer of roof covering weighing 3 pounds per square foot (0.1437
kN/m2)or less over an existing, single layer of roof covering.
Replacement equipment shall be anchored and braced in accordance with the requirements
of the International Building Code.
Sections 706.3 & 706.3.1 —Reroof Permits
SUMMARY OF REVISIONS:
Captures all parapets and precludes compliance with reduced forces.
OREGON REVISIONS:
706.3 Additional requirements for reroof permits. The requirements of this section shall apply to
alteration work requiring reroof permits.
706.3.1 Bracing for unreinforced masonry bearing-wall parapets. Where a permit is issued for
reroofing for more than 25 percent of the roof area of building assigned to Seismic Design
Category D, E or F that has parapets constructed of unreinforced masonry, the work shall include
installation of parapet bracing to resist the reduced International Building Code level seismic
forces as specified in Section 301.1.4. 1 of this code, unless an evaluation demonstrates
compliance of such items using the reduced International Building Code seismic forces as
specified in Section 301.1.4.2.
Chapter 8
Section 807.5—Existing Structural Elements Resisting Lateral Loads
SUMMARY OF REVISIONS:
Precludes compliance with reduced forces.
Page 9 of 11
OREGON REVISIONS:
807.5 Existing structural elements resisting lateral loads. Alterations affecting the demands or
capacities of existing elements of the lateral load-resisting system shall be evaluated using the wind
provisions of the International Building Code and the r IBC-level seismic forces. Any
existing lateral load-resisting structural elements whose demand-capacity ratio with the alteration
considered is more than 10 percent greater than its demand-capacity ratio with the alteration
ignored shall be brought into compliance with those wind and seismic provisions. In addition, the
alteration shall not create a structural irregularity prohibited by ASCE 7 unless the entire structure
complies with Section 301.1.4.2. For the purposes of this section, comparisons of demand-capacity
ratios and calculation of design lateral loads, forces and capacity shall account for the cumulative
effects of additions and alterations since the original construction.
Chapter 9
Section 907.4.2 Substantial Structural Alterations
SUMMARY OF REVISIONS:
Precludes compliance with reduced forces.
OREGON REVISIONS:
907.4.2 Substantial structural alteration. Where more than 30 percent of the total floor and roof
areas of the building or structure have been or are proposed to be involved in structural alteration
within a five-year period, the evaluation and analysis shall demonstrate that the altered building or
structure complies with the International Building Code for wind loading and with reduced IBC-level
seismic forces The areas to be counted toward the 30 percent shall be those areas tributary to the
vertical load-carrying components, such as joists, beams, columns, walls and other structural
components that have been or will be removed, added or altered, as well as areas such as
mezzanines,penthouses, roof structures and in-filled courts and shafts.
Chapter 10
Section 1001.3.1 —Partial Change of Occupancy Classification
SUMMARY OF REVISIONS:
Requires compliance with structural provisions of 1007 in addition to the occupancy change
requirements of 1012.
OREGON REVISIONS:
1001.3.1 Partial change of occupancy classification. Where a portion of an existing building is
changed to a new occupancy classification, Sections 1007 and 1012 shall apply.
Section 1007.3.1 —Change of Occupancy(Work Area Method)
SUMMARY OF REVISIONS:
Establishes elevated seismic hazard improvement standards for change of occupancy.
Page 10 of 11
OREGON REVISIONS:
1007.3.1 Compliance with the International Building Code level seismic forces. Where a
building or portion thereof is subject to a change of occupancy that results in the building being
assigned to a higher occupancy category based on Table 1604.5 of the International Building
Code; or where such change of occupancy results in a reclassification of a building to a higher
hazard category as shown in Table 912.4; or where a change of a Group M occupancy to a Group
A, E, I 1, R 1, R 2 or R 4 occupancy with two thirds or more of the floors involved in Level 3
level seismic forces as specified in Section 101.5.1.1 for the new occupancy category Table 1007.3
or when the total building occupancy load is increased by more than 150 occupants, the
building shall comply with the seismic improvement standards of Table 1007.3 as defined in
Section 301.1.4.1 for the new occupancy category.
Exception:
Group M occupancies being changed to Group A, E,I 1,R 1,R 2 or R 1 occupancies for building)
less than six stories in height and in Seismic Design Category A,B or C.
Where approved by the code official, specific detailing provisions required for a new structure are
not required to be met where it can be shown that an equivalent level of performance and seismic
safety is obtained for the applicable occupancy category based on the provision for reduced
International Building Code level seismic forces as specified in Section 301.1.4.2.
percent of the total building floor area and the new occupancy is not classified as Occupancy
Category IV. For the purpos s of this exception, b-' .••b •. - - a a • - , • •• •-
not included in the same occupancy category, shall be subject to the provisions of Section 1601.5.1
- - -- - •. . E a'•b ede. The cumulative effect of the area of occupancy changes shall
be considered for the purposes of this exception.
Unreinforced masonry bearing wall buildings in Occupancy Category III when assigned to Seismic
Design Category A or B shall be allowed to be strengthened to meet the requirements of Appendix
Chapter Al of this code [Guidelines for the Seismic Retrofit of Existing Buildings(GSREB)].
TABLE 1007.3
Seismic Hazard Categories and Structural Improvement Standard d
RELATIVE HAZARDb' OSSC OCCUPANCY SEISMIC IMPROVEMENT
CLASSIFICATION STANDARD°
I(Highest Standard) A,E,I-2,1-3,H 301.1.4.1
2 R-1,R-2,R-4,SR,1-1,1-4 301.1.4.1
3 B M 301.1.4.2
4 F-1,F-2,S-1,S-2 301.1.4.2
5(Lowest Standard) R-3,U 301.1.4.2
Notes:
a) Required improvements shall be made such that the entire building conforms to the indicated standard.
b) Where the area of the new occupancy with a higher hazard category is less than or equal to 33 percent of the total building floor area,
and the total occupant load for the building is not increased by more than 150 occupants(or 10 percent of the existing occupant load,
whichever is greater)the building does not require structural improvement unless required by other provisions of this code.
c) Where a change in occupancy results in the addition of more than 150 occupants to the building(or 10 percent of the existing occupant
load,whichever is greater),the building shall be structurally improved based the Seismic Improvement Standard for the occupancy
classification of the majority of the added occupants.
d) For the purposes of this section,multiple changes in occupancy and occupant load are considered cumulative.The cumulative effects of
the building area occupancy changes and occupant load changes shall be considered based upon the established legal occupancy on April
1,2014.
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